Update `Launcher` and `JarFile` to correctly deal with Windows UNC
paths.

Fixes gh-1641

When logging.level.* is set in external configuration they can now
contain placeholders.

Fixes gh-1680

Closes gh-1671

Closes gh-1660

(Cherry picked from commit bebbe92f)
Fixes gh-1633

Closes gh-1474

In addition to requiring the Servlet API to be on the classpath,
MetricFilter requires spring-web to also be on the classpath as it
extends OncePerRequestFilter. This commit updates the auto-configuration
for MetricFilter so that it will be disabled in the absence of a 
dependency on spring-web.

Fixes gh-1664

Some weird looking test failures led me to track this down.
If the user changes the prefix for metric names, he probably wanted
to change the keys as welll (otherwise 2 repositories can use the
same key, which is why the test was failing for me). We can do that
in an afterPropertiesSet().

Previously, the Gradle plugin’s ProjectLibraries produced a new library
for every file dependency, even if the dependencies where on the same
file. This would lead to a repackaging failure due to multiple
libraries having the same name.

This commit updates ProjectLibraries to treat file dependencies on the
same file as a single library, thereby resolving the name clash.

Fixes gh-1646

See gh-1631

The file name can now be overridden at runtime with a System property or
environment variable named "PIDFILE" (or "pidfile").

Fixes gh-1579

...so that application startup that fails because of an Error (for
instance NoClassDefFoundError) won't be swallowed.

Fixes gh-1645

Fixes gh-1489

Fixes gh-1631

Fixes gh-1636

Closes gh-1621

To make it easier to identify the source of the competing LoggerFactory
implementation, this commit updates the exception message to include
the code source location of the offending class.

Closes gh-1630

Closes gh-1643

Closes gh-1627

Without the @Param annotations, using either of the search URIs would
resulted in a 400 response and an error describing the lack of @Param
annotation.

See gh-1627

Update Tomcat ServerProperties to support the RemoteIpValve portHeader
property.

Fixes gh-1616

The `protocolHeader` and `remoteIpHeader` no longer have default values
and must be opt-in.

Fixes gh-1624